Well casing perforator



0d' 21 1947-, M. SCHLUMBERGER 2,429,240

WELL CASINGv -PERFORATOR Original Filed Jan. 23,1940 2 Sheets-Sheet l ,4 y ATTORNEY.

Oct. 2l,A 1947. M SCHLUMBERGER A 2,429,240

WELL cAsING PERFORATOR Original Filed Jan. 23, ,1940 2 Sheets-Sheet 2 INVENTOR Marce] cblumbeyer;

ATTORNEYS Patented Oct. 2l, 1947 WELL cAsrNG rrzi'trolwron Marcel Schlumberger, saint Gaudens, nau- Y Garonne, France vested in the Attorney General of the United States Original application January 23, 1940, Serial No.

315,157, 4now Patent No. 2,381,081, dated August 7, 1945. Divided and this application July 23, 1941,' Serial No. 403,650. In France February 18 Claims. 1 v'I'his yinvention relates to ring devices and more particularly to new and improved, apparatus for perforating well casings and the like.

Copending application Serial No. 315,157, filed January 23,-1940, for Gun perforator, of which this application is agdivision, is addressed to perforating apparatus comprising an assembly of similar units each of which is provided with a plurality of gun bores and cartridge chambers therein. Each unit includes igniting means for each gun therein and the apparatus is so designed that when the units are assembled, at least one continuous ignition path extends through the perforator.

This application is directed to similar apparatus in which the units are so designed that, when assembled, the axes of the guns therein lie along a helix about the periphery of the perforator.

It is an object of the invention, accordingly, to provide new and improved well casing perforating apparatus comprising a plurality of assembled similar units in which the axes of the gunsin the respective units lie along a helix about the perforator assembly.

Another object of the invention is to provide new and improved means for firing the guns in a well casing perforator of the above character in successive order.

A further object of the invention is to provide new and improvedwell casing apparatus of the above character in which a given interval of time elapses between the iiring of each adjacent gun.

Another object of the invention is to provide 'means for indicating at the surface of the earth that a gun in the well casing perforator has been fired.

Other features of the invention will become apparent from the following detailed description of several preferred embodiments taken in connection with the accompanying drawings, in which:

. Fig. 1 is a View in longitudinal section, taken` along line I--l of Fig. 3, and looking in the direction of the arrows, through a well casing perforator constructed according to the present invention;

Fig. 2 is a view in longitudinal section, taken along line 2-2 of Fig. 3, looking in the direction of the arrows and illustrating two of the perforating units of the well casing perforator;

Fig. 3 is a view in section taken along line 3-3 of Fig. 1, looking in the direction of the arrows;

Fig. 4 is a view in vertical section of a modified form of the invention;

Fig. 5 is a cross-sectional view taken along line 2 5-5 of Fig. 4, looking in the direction of the arrows;

Fig. 6 is a crosss-sectional view taken along line 6--6 of Fig. 4;

Fig. 7 is'a view in plan of a detail of the apparatus shown in Fig. 4;

Fig. 8 is a view in section of the detail shown in Fig. 7 taken along line 8-8 thereof and looking in the direction of the arrows;

Fig. 9 is a view in longitudinal section through a further modification of the invention; and

Fig 10 is a cross-sectional'view taken along line l0-l0 of Fig. 9, looking in the direction of the arrows.

Figs. 1, 2 and 3 illustrate one form of the invention in which each of the perforator units comprises three longitudinally extending cartridge chambers, vthe axes of Which form the apices of an equilateral triangle about the axis of the unit, each one of which is provided with a laterally extending gun barrel passing through the longitudinal axis of the unit. The units are so designed that when assembled to form a well casing perforator,` the axes of the guns lie upon a helix about the periphery, and the guns are adapted to be fired by electrical igniting circuits extending through each unit in the perforator assembly.

Referring to Figs. 2 and 3, one of the perforator units I0- is shown, in which are provided three cartridge chambers Ila, lib and llc, the axes of which are located parallel to the axis of the unit I0, forming the respective edges of an equilateral prism coaxial thereto. The cartridge chambers Ila, lib and Hc are provided at their lower extremities with longitudinally extending conduits l2a, I2b and I2C, which communicate with a plurality of laterally extending gun barrels I3a, |317 and l3c, the axes of which are disposed at an angle of with respect to each other. In order that the gun barrels |3a, l3b and I3c may lie in different transverse planes through the perforator unit I0, the conduits |2a, I2b and 2c, respectively, are made of different lengths.

Considering now Fig. 1, a cartridge I4 is shown in position in the cartridge chamber lib, for example, and it is provided with a thin walled forward portion i5 forming a, powder chamber I6 and a thicker walled rear portion I'l forming a passage I8. The front end of the ycartridge I4 is closed by a suitable closure member I9. Within the passage I8 is disposed a hollow tubular conducting member 20 which Vis provided with a metal plate 2| at the upper extremity thereof, the

perforator.

f 3 outer surface of both the plate 2| and the tubular member` being covered with suitable insulating material 22, i

Disposed within the tubular member 20 and concentric therewith is a conducting rod'23 which extends for a short distance beyond the tubular member 20 into the chamber I8 in the cartridge I4. The conducting rod 23 is provided at its upper extremity with a metal plate 24, thefsur'face of both being encased in suitable insulating material 25. A wire lament 2B for igniting the powder charge within the chamber I6 is connected at one end to the tubular `member 2|l and at its other end to the conducting rod 23 and the energizing circuit therefor is traced through the conducting plate 24, the conducting rod 23, the wire filament 26, the tubular conducting member 20 and the plate 2|.

ki4 of shots which are to be fired into the casing. 'Ihe topmost unit I3 is then screwed to a connector `unit 34' by means of which the respeci tive'igniting circuits in the perforator apparatus may be electrically connected to corresponding conductors in the supporting cable (not shown). The connector unit 34 is of a special type which l is adapted to break an igniung circuit each time that a gun is fired, thereby indicating to the operator at the surface of the earth that the ilring operationY has been succesful. Circuit breaking means of this character is used in each of the three igniting circuits in the well casing Within the perforator unit are provided v three longitudinally extending bores'21, the axes of which are disposed substantially at the apices of an equilateral triangle, and each of which is adapted to accommodate a conducting rod 28.

The rods 28 are provided with pointed ends whichprojecty slightly beyond the upper and lower faces of the perforator unit l0 and they are insulated therefrom by sleeves of suitable insulating material 29.

As shown in greater detail in Fig. 3, each of the conducting plates 24 is provided with a laterally extending portion 30 and each conducting plate 2| is provided with a similar projecting portion 3|. The cartridge I4 is so assembled that the projection 30 on the plate 24 is disposed substantially 180 away from the projection 3| on the plate 2| and it is inserted into the cartridge chamber Hb in such fashion that the projection 3| on the plate 2| is disposed adjacent the pointed end of one of the rods 28.

The perforator units are so designed that when the unit I0, for example, is threadedly secured to the unit Ill', the pointed end of the conducting rod 28 of the perforator unit l0 pierces the insulating layer covering the projection 30' of the conducting plate 24' while the pointed end of a similar conducting rod in the perforator unit I0 makes an analogous connection with the conducting plate 2|'.

It will be apparent, therefore, that, in operation, current will flow through the conducting plate 24, the conducting rod 23, the iilament 26, the tubular conducting member 2,0 and the conducting rod 23 in the perforator unit l0 to the contact plate 24' of the next lower perforator unit l0'. In this fashion current is supplied to each series of cartridges i4 in the assembled perforator.

It will be noted further that in this embodiment of the invention the current path is not along a line parallel to the axis of the assembled 0n the contrary, the current flows along a, line parallel to the axis of the perforator unit I3, then along a line located at an angle of approximately 115 away and parallel to the axis of the next succeeding perforator unit ill and so on through the respective units of the assembled apparatus.

In order that the cartridges I4 may be readily inserted within the respective cartridge champerforator. For'the sake of simplicity, however, only one ignitingV circuit and the circuit breaking means therefor are shown in Fig, l.

Referring again to Fig. 1, the conductor 35 in .the supporting cable is secured by means of a to one contact element 4| of a conventional type mercury switch 42 which is vertically disposed within a sleeve 43 made of exible material such as rubber, forexample, and which contains just enough mercury to remain in contact with the contact element 4| when the connector unit 34 is at rest.

The'other contact element 44 of the switch 42 is connected by means of va conductor 45 to a conducting block 46. The block 46 is connected by means of the conductors 41 and 48 to an insulated conducting rod 4S which is adapted to engage the projection 30 on the conducting plate' 24 in the first perforator unit l0.

When the assembled perforator is at rest, the contact element 4'| dips into the mercury in the switch 42 so that electric current ows normally therethrough to the firing circuit. However, when a shot is red, the entire perforator assembly sustains a violent shockwhich displaces the mercury 'and temporarily breaks the electrical firing circuit. The break in the circuit may be readily indicated in any suitable manner, as, for example, by listening to a telephone receiver connected in the circuit at the surface of the earth. In this fashion, itis possible to check the firing of the shots by noting the break produced in the electrical circuit by the shock sustained when a gun is red.

In operation, the filaments in the cartridges in each igniting circuit are ignited successively by adjusting the value of the current iiowing therethrough. To this endfthe lgniting filaments of `fdierent electrical characteristics are used, the 'lov/errnost one in the perforator being designed gun bore E31; after the projectile therein has been fired also tends to ground the conducting rod 23, in which case the igniting circuit is completed directly through the conducting bore hole liquid.

In the embodiment shown in Fig. 4, a disc 50 is secured to the bottom of the perforator unit ||i by means of a conventional tap screw 5|. The disc 50 is provided with internally threaded recesses 52 therein within which are secured the cartridges for firing the guns. Each threaded V recess 52 communicates through a narrow passage 54 with a larger sector-shaped recess 55 formed in the upper face of the disc 50, within which is disposed a metallic plate 56 of approximately the same shape, which is enclosed in suitable insulating material 51.

As shown in greater detail in Figs. 'l and 8, a small portion of the insulation is removed from the upper face of the plate 56, forming a slot 58 therein and part of the insulation is removed from the lower face of the plate 56 to form a small hole 59 therein which is adapted to register with the narrow passage 54 in the disc 50. The connector element 34- is provided with a similar disc 56aand corresponding parts have been designrat'ed with corresponding reference numerals with the subscript a.

The cartridge 53 is provided with an upper closure member 60 having'a passage 6I therein, within which is disposed an insulating sleeve 62 having a contact rod 63 therein. The cartridge 53 alsohas a lower closure member 64 made of suitable insulating material, in` which is inserted a conducting rod 65. The conducting rod 65 is enclosed in a sleeve 66 of insulating material within a passage 61 in the'perforator unit l0 and itis provided with a pointed end which is adapted to project through one of the slots 58 into engagement with one of the plates 56 in the disc 56. A wire filament 68. is connected between the contact rod 63 and the contact rod 65, which filament serves to ignite the powder in the cartridge 53.

When the perforator units I0, I0', etc., are assembled as shown in Fig. 4, it will be noted that the contact rods 65 on the cartridges 53 in the perforator I6 extend through the upper slots 58 in the insulation 51 into engagement with the contact plates 56. \Also, the contact rods 63 of the cartridges 53 in the perforator unit I0 project through the passages 54a in the disc 50a into engagement with the contact plates 56a as shown in Fig. 5. Similar connections obtain between 'the perforator units I!) and I6 as illustrated in Fig. 6 so that three continuous ring circuits are produced in the assembled perforator.

It will be apparent that in this modification the successive cartridges 53 through which the ring current passes are located in diierent radial planes, the angle between any two successive radial planes being approximately equal to the -angle subtended by the contact plate 56. The successive cartridges 53 are ignited in the same manner as described above in connection with the cartridges -shown in Figs. 1-3.

Figs. 9 and 10 illustrate another embodiment of the invention in which ignition is transmitted 'automatically from one .cartridge `to another cartridge located along a different generatrix of the perforator. kIn this embodiment,each cartridge -69 is provided with a lower closure portion 'I0 having a very narrow bore 1I formed therein. The bore 1| is adapted to register with a narrow inclined passage 12 formed in the perforator unit I0 which extends to the cartridge '69' in the next perforator unit I il which is located on a diffrent generatrix.

In this embodiment, the guns in the uppermost perforator unit i0 are preferably fired electrically and to this end the cartridge 69 is provided with an igniting filament 14 grounded at one end to the metallic cartridge case 15 and connected by means of an insulated conductor 16 to the contact rod 49 which isv connected to the conductor 35 in the supporting cable.

When the cartridge 69 is fired by passing electrical current through the igniting filament 14, the powder gases pass through the narrow bore 1| in the lower closure member 10 of the cartridge 69 to the inclined passage 12, where they are allowed to expand. The expanded gases then pass to the upper end of the cartridge 69 in the next perforator unit l0' where they iiow through a restricted aperture 11' and through a passage 18 to the charge of powder contained within the cartridge 69', which is ignited thereby.

The passage through the restricted bore 1I and the subsequent expansion in the inclined passage 12' produce a delay in-the transmission of ignition so that a certain interval of time elapses between the ring of the successive cartridges.

" From the foregoing, it will bel/apparent that l' the `invention provides new and improved well casing perforating apparatus which is characterized by simplicity and increased safety of operation. Moreover, the applicants novel circuit breaking means provides an indication at the surface of the earth each time that a `gun is red, thus enabling the operator to ascertain if the apparatus is functioning properly.

While several specic embodiments7 have been described in detail hereinabove, the invention is not intended to be limited thereto, but is susceptible of numerous changes in form and detail withperforator, and igniting means for each of said chambers, said igniting means being so associated with one another as to form a complete ignition cally connected with one another so as to form a.

complete ignition path extending through the perforator. i

3. A well casing perforator comprising a piurality of units detachably assembled in consecutive series in a longitudinal direction, each unit being provided with at least one longitudinally extending powder chamber having at least one gun barrel communicating therewith, the axes of the powder chambers in adjacent units being angularly spaced about the axis of the perforator, an explosive charge in each of said powder chambers, means providing restricted communication between said respective powder chambers and means for igniting the explosive charge in a powder chamber at one end of said perforator, whereby ignition will be transmitted successively to said respective powder chambers.

4. A well casing perforator which comprises, in combination, a. plurality` of units detachably assembled in consecutive series in a longitudinal direction, each unit being provided with at least two longitudinal powder chambers and at least one gun barrel for each chamber, and igniting means for each of said chambers, the igniting means of one chamber being adapted to be connected automatically, upon assembly of said units, to the igniting means of a chamber of the next unit located on a different longitudinal' line, so as to constitute at least two complete ignition paths extending` through said series of units, each along a non-rectilinear line.

5. A well casing perforator which comprises, in combination, a plurality of units detachably assembled in consecutive series in a longitudinal direction, each unit being provided with at least two longitudinal powder chambers and at least one gunbarrel for each chamber, and powder ignition means for eachwof said chambers, the ignition means of one chamber being adapted t be operatively connected, upon assembly of said units, to the ignition means of a chamber of the next unit located on a different longitudinal line so that each series of chambers thus connected together is located on a helix.

6. A well casing perforator which comprises at least one body member having a longitudinal axis, provided with at least two cartridge chambers having axes parallel to the axis of said body member and located in peripheral regions thereof, at least two longitudinally extending conduits communicating with each of said chambers, respectively, and means forming at least one barrel hole extending from each of said conduits to the outer wall of said body member i a direction transverse to its axis and passin through the central portion of the body member.

7. A well casing perforator which comprises,

' in combination, a plurality ofmetal units, de-

tachably assembled together in consecutive series in a longitudinal direction, each unit being provided with at least one longitudinally extending cartridge chamber therein, having at least one gun barrel communicating therewith, a cartridge in said chamber, an igniting filament in the cartridge, a pair of contacts on said cartridge and connected to said igniting filament, and at least one insulated conducting rod extending through said unit, one end of said conducting rod being in engagement with one of said cartridge contacts and the other end of said rod being in engagement with one of the contacts on the cartridge in the corresponding powder chamber in the next unit, and the conducting rods and -cartridge contacts in the respective units being adapted to cooperate to form at least one complete ignition circuit extending through the perforator.

8. A well casing perforator which comprises, in combination, a plurality of metal units detachably assembled together in consecutive series in a longitudinal direction, each umt being provided with at least one longitudinal cartridge chamber opening into'one face thereof and extending to a distance from the other end thereof, and at least one gun barrel for said chamber, extending transversely of said longitudinal direction, a cartridge in said chamber, including a tubular metal casing closed at both ends, an explosive charge in said tubular casing, two longitudinal rods extending through the rear portion of said casing, said rods being insulated from each other and from the cartridge casing, a filament connected to the ends of said rods within the casing, two superposed metallic plates connected to said rods, respectively, adjacent the outer face of said rear portion of the cartridge casing, and adapted to be retained between said end part ofV the cartridge and the front face of the preceding unit, an insulating layer on each face of said plates, a conducting rod having sharp pointed ends extending throughout each unit for connecting one of said plates with another plate of the next unitupon assembly of said units, said insulating layers being adapted to be crushed by the explosion of the charge in the cartridge, whereby the metal of each cartridge case and therefore the metal of the corresponding unit will be connected directly with a condcting rod` of the preceding unit when a cartridge in the rst mentioned unit is tired.

9. A well casingvperforator which comprises, in combination, a plurality of metal units'detachably assembled together in consecutive series in a longitudinal direction, each unit being provided with at least one longitudinal cartridge chamber opening into one face thereof and extending to a given distance from the other end thereof and at least one barrel hole for said chamber extending transversely of said longitudinal direction, a cartridge in said chamber, including a tubular casing closed at both ends, a charge of powder in said tubular casing, two longitudinal rods extending through the rear portion of said casing, an insulating layer around each of said rods, a nlament connected to the ends of said rods within said casing, two super` posed metallic plates of disymmetrical shape connectedto said rods, respectively, adjacent the outer face of said rear portion of the cartridge casing in different angular positions, respectively, and adapted to be retained between said end part of the cartridge and the front face of the preceding unit, an insulating layer on each face of each of said plates, a conducting rod having sharp pointed ends extending throughout each unit for connecting one of said plates with the plate of the next unit located in a different angular position, upon assembly of said units, s aid insulating layers being adapted to be crushed by explosion of the powder in said cartridge, whereby the metal of each cartridge vcasing and therefore the metal of the corresponding unit will be connected directly with a conducting rod of the preceding unit when a cartridge in the rst mentioned unit is red.

10. A well casing perforator which comprises, in combination, a plurality of metal units detachably assembled together in consecutive series in a longitudinal direction, each unit being provided with at least one longitudinal cartridge chamber opening into one face thereof and extending to a distancefrom the other end thereof and at least one barrel hole for said chamber, extending transversely of said longitudinal direction, and intermediate the inner end of said chamber and said other end of said unit, a small conduit connecting saidV chamber and the corresponding barrel, a cartridge in said chamber,

.including a tubular casing closed at both ends,

a charge of powder in said tubular casing, two

longitudinal rods extending through the rear portion of said casing, an insulating layer around eachpf said rods, a filament connected to the ends of said rods within the casing, two superposed metallic plates connected to said rods, respectively, against the outer face of said rear portion of the cartridge casing and adapted to be retained between said rear portionof the cartridge and the front face of the preceding unit, an insulating layer on each face of each of said plates, a conducting rod having sharp pointed ends extending throughout each unit for connecting one of said plates with another plate of the next unit, upon assembly of said units, said insulating layers being adapted to be crushed by the explosion of the powder in the cartridge, whereby the metal of each cartridge casing and therefore the metal of the corresponding unit will be connected directly with a conducting rod of the preceding unit when a cartridge in the iirst mentioned unit is fired.

11. A well casing periorator which comprises, in combination, a plurality of metal units detachably assembled together in consecutive series in a longitudinal direction, each unit being provided with at least two longitudinal cartridge chambers forming each a blind hole extending from the rar end face of said unit to a distance from the front end thereof and at least one barrel hole for each of said chambers extending transversely of said longitudinal direction, a cartridge in said chamber comprising a tubular casing closed at both ends and tted in said chamber, a charge of powder in said tubular casing, an ignition conductor extending throughout each of said cartridges,' said unit being provided with a narrow passage extending from each cartridge chamber to the front end of said unit, a rod on said cartridge extending through said last mentioned passage and connected with said conductor, a second rod on the other end of said cartridge of the next unit located in a different radial plane.

12. A well casing perforator which comprises. in combination, a plurality of metal units detachably assembled together in consecutive series in a longitudinal direction, each unit being provided with at least two longitudinal lcartridge chambers forming each a blind hole extending from the rear end iace of said unit .to a distance from the front end thereof and at least one barrel hole for each of said chambers extending transversely of said longitudinal direction, a cartridge in said chamber, comprising a tubular casing closed at both ends and fitted in said chamber, a charge of powder in said tubular casing, an ignition conductor extending throughout each of saidv cartridges, said unit being provided with a narrow passage extending from each cartridge chamber to the front end lof said unit, a rod mounted on said cartridge and extending through said last mentioned passage, a second rod mounted on the other end of said cartridge, said second rod being connected with said conductor and projecting from the rear end face of said cartridge,

a plurality of sector-shaped transmission mem-- the shock produced by the explosion of said charge for providing an indication that the explosion has taken place.

14. A well casing perforator comprising a body adapted to be lowered into a bore hole and having at least one explosive charge therein, an electric circuit for igniting said explosive charge, and a mercury switch in said circuit for breaking the circuit when the charge is exploded to indicate that the explosion has taken place.

15. A well casing perforator which comprises, in combination, aplurality of units detachably assembled in consecutive series, each unit being provided with at least one powder chamber having an explosive charge therein, and at least one gun barrel for said chamber, electric igniting means in each of said units for igniting said explosive charge inthe chamber, said igniting means being adapted to be interconnected automatically from one unit to the next upon assembly of said units so as to constitute at least one ignition circuit extending therethrough, and switching means having contacts rendered operative by the shock of the explosion for temporarily breaking said circuit every time an explosive charge in one of said chambers is ignited.

16. A well casing perforator which comprises, in combination, a plurality of units detachably assembled in consecutive series, each unit being provided with at least one powder chamber having an explosive charge therein, and at least one gun barrel for said chamber, electric igniting means in each of said units for igniting the explosive charge in said chamber, said igniting means being adapted to be interconnected automatically from one unit to the next upon assem- 'bly of said units so as to constitute at least one ignition circuit extending therethrough, and a mercury switch in said circuit for temporarily breaking said circuit every time one of said explosive charges is ignited.

17. In a well casing perforator including a body adapted to be lowered into a bore hole, at least one explosive charge in the body, and an electric circuit for igniting said explosive charge. the combination of switching means having contacts in said circuit and responsive to the shock produced by the explosion of said charge for pro viding an indication that the explosion has taken place.

18. In a circuit for igniting an explosive charge in a gun adapted to be lowered into a bore hole, the combination of switching means in the gun, said switching means having contacts responsive to the shock produced by the iiring of the explosive charge for providing an' indication that the iring of said charge has taken place.

MARCEL SCHLUMBERGER.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS 

